This short book consists of a compilation of several lectures
by Stephen Hawking. Many of the ideas from them appear in several
of his past books. Hawking attempts to explain sophisticated
and complex mathematical ideas in an unsophisticated, perhaps
childlike (but charming) way. He briefly covers the history of
ideas about the universe from Aristotle, Augustine, Newton, Einstein,
Hubble, and Feynman. He then explains the Big Bang, black holes,
and space-time and incorporates these thoughts into the search
for a unified theory of everything. Although Hawking does not
announce the arrival of the Theory of Everything, he does explain,
in simple metaphors, the flavor of what such a theory would encompass.

One of the more important concepts of his involves the idea
that the "beginning" of the universe does not necessarily
imply a singularity (or in holistic terms, a oneness). If we
wish to hold consistency with quantum mechanics (the most successful
scientific theory to date) then a no-boundary condition would
best describe the beginning. Needless to say, this contradicts
many religious ideas about a creation (although he empathizes
that these ideas represent only a proposal).

Hawking represents one of the most brilliant theoretical scientists
of our time. He advocates the idea of communicating the ideas
theoretical science in a way to make it understandable, in principle,
to everyone, not just scientists. Hawking has an acute awareness
of the religious impact of his theoretical studies and explains
in a clear but inoffensive way that the universe does not conform
to the common belief of an all powerful Creator.

A few quotes from the book:

An expanding universe does not preclude a creator, but it
does place limits on when He might have carried out his job.

We now know that our galaxy is only one of some hundred thousand
million that can be seen using modern telescopes, each galaxy
itself containing some hundred thousand million stars.

This behavior of the universe [expanding universe] could have
been predicted from Newton's theory of gravity at any time in
the nineteenth, the eighteenth, or even the late seventeenth
centuries. Yet so strong was the belief in a static universe
that it persisted into the early twentieth century. Even when
Einstein formulated the general theory of relativity in 1915,
he was sure that the universe had to be static.

The present evidence, therefore, suggests that the universe
will probably expand forever. But don't bank on it.

Black holes are one of only a fairly small number of cases
in the history of science where a theory was developed in great
detail as a mathematical model before there was any evidence
from observations that it was correct.

Quantum mechanics allows the universe to have a beginning
that is not a singularity. This means that the laws of physics
need not break down at the origin of the universe.

In the case of the whole universe, one can show that this
negative gravitational energy exactly cancels the positive energy
of the matter. So the total energy of the universe is zero.

One could say: "The boundary condition of the universe
is that it has no boundary." The universe would be completely
self-contained and not affected by anything outside itself. It
would be neither created nor destroyed. It would just be.

I should emphasize that this idea that time and space should
be finite without boundary is just a proposal. It cannot be deduced
from some other principle.

A scientific theory is just a mathematical model we make to
describe our observations. It exists only in our minds. So it
does not have any meaning to ask: Which is real, "real"
or "imaginary" time? It is simply a matter of which
is a more useful description.

If the universe is really completely self-contained, having
no boundary or edge, it would be neither created nor destroyed.
It would simply be. What place, then, for a creator?

If one liked, one could ascribe this randomness [quantum uncertainty]
to the intervention of God. But it would be a very strange kind
of intervention. There is no evidence that it is directed toward
any purpose. Indeed, if it were, it wouldn't be random.

Our aim is to formulate a set of laws that will enable us
to predict events up to the limit set by the uncertainty principle.

If the no boundary proposal is correct, He [God] had no freedom
at all to choose initial conditions.

The people whose business it is to ask why-- the philosophers--
have not been able to keep up with the advance of scientific
theories.